Operating mechanism for line sectionalizers and the like



Dec. 14, 1954 M WALLACE ET AL 2,697,149

OPERATING-MECHANISM FOR LINE-SECTIONALIZERS AND THE LIKE Filed July 25. 1949 BYQ ATTORNEY United States Patent C) OPERATING MECHANISM FOR LINE SECTIONALIZERS AND THE LIKE James M. Wallace, East McKeesport, and Alvin W. Ogg,

Pittsburgh, Pa., assignors to Westinghouse Electric Corporation, East Pittsburgh, Pa., a corporation of Penn- Sylvania Application July 26, 1949, Serial No. 106,887

17 Claims. (Cl. 200-108) Our invention relates to improvements in line-sectionalizing equipment for distribution-systems, particularly for radial-type rural power-lines of from 2.4 to kilovolts. More particularly, our invention relates to a novel kind of operating-mechanism, which is designed not only for use in line-sectionalizers, but also so as to be interchangeable with reclosing circuit-breakers, which differ from sectioualizers mainly in the greater current-interrupting ratings of the breaker-contacts, and in the reclosing operation which is used with the reclosers but not with the sectionalizers.

The object of our invention is to produce or provide an entirely new and redesigned operating-mechanism of the class described, having an entirely new toggle-linkage arrangement, involving various novel features and advantages, including the following: a peculiar toggle-andlnkage motion is used, which results in an extremely light latch-load, and a self-locking feature which holds the mechanism open, by gravity, once it has opened, thus avoiding dependence upon latches and springs, which may fail and let the mechanism reclose; a parallel-link guidingmeans is used for the moving contacts, which is made possible by hanging the assembly from the top, with plenty of insulation, thus helping the gravity-operation, and in fact automatically providing gravity-operation; and the lever-system is completely trip-free in all positions. In addition, our novel operating-mechanism adds extreme simplicity and low cost to its other operational advantages.

With the foregoing and other objects in view, our invention consists in the systems, combinations, structures, parts, and methods of design and operation, hereinafter described and claimed, and illustrated in the accompanying drawing, wherein Figure 1 is a diagrammatic view of circuits and apparatus illustrating the kind of system in which our invention is used,

Fig. 2 is a simplified cross-sectional view through the counting-means and through the operating-mechanism of a sectionalizer illustrative of our invention,

Figs. 3, 4 and 5 are linkage-diagrams showing the operation of the various parts, in the closed, tripped, and open positions, respectively, and

Fig. 6 is a force-diagram corresponding to Fig. 3.

In Fig. l, we show our invention applied to a rural power-line 5 of the type described, which is fed from a power-source 6 through a diagrammatically indicated recloser 7, having a normally closed breaker-contact 8, and an operating-coil 9, both connected in series with the line 5. The recloser has an armature 11 which is mechanically connected, at 12, to a block 13 which represents any suitable counter-and-lockout mechanism, which counts the number of rapidly repeated contact-openingand-reclosing operations, and after a predetermined number of such operations locks out the recloser by thereafter holding the contact 8 in its open position, until the recloser is manually reset. It will be understood that the recloser-contact 8 is normally closed but opens in response to a predetermined over-current-condition in the coil 9. The opening of the contact 8 deenergizes the coil 9, and when the coil 9 is deenergized, the recloser-contact 8 automatically recloses itself, until the counter-mechanism 13 becomes effectively operative and holds the contact 8 in its open position. There are a number of such reclosers on the market, and their specilic construction constitutes no part of our present-invention, unless the mechanism 13 is designed so as to include our sectionalizer-operating mechanism which will be subsequently described. It is 2,697,149 Patented Dec. 14, 1954 believed, therefore, that the diagrammatic recloser-illustration in Fig. 1 is sufliciently clear without further explanation or illustration.

The rural power-line 5 may extend out, either in a single branch, or in a plurality of branches 15 and 16, each branch usually supplying a number of customers located at various points distributed along the line. Most of the faults which will occur on such a line are faults which will clear themselves as soon as voltage is removed from the line, although sometimes a fault may require a certain length of time, or a certain number of successive openings and reclosures of the recloser 7, in order to burn oif or clear the fault. The recloser 7 protects such a line by more or less rapidly opening and reclosing its breaker- Contact 8 for a predetermined number of times, such as 4 or 5 times, after which, if the fault has not then cleared itself, the fault is considered to be a permanent fault and the recloser permanently opens its contact 8.

Since a line 5 of the type in question, or its several branch-lines 15 and 16, usually serve a considerable number of customers, it has been recognized as being desirable to use one or more sectionalizers for increasing the number of points, along the line, at which the circuit can be disconnected in the event of a permanent fault which will not clear itself, thus limiting the number of customers, or the amount of the circuit, affected by any permanent fault.

Fig. 1 illustrates a typical situation in which a sectionalizer 17 is inserted at some intermediate point along the length of the branch-line 15, while a similar sectionalizer 18 is inserted at some intermediate point along the branchline 16. Each sectionalizer, such as 17, comprises a series-connected operating-coil 19, and a normally closed, series sectionalizer-contact 20, both of which are connected in series with the associated branch-line such as 15. The current-coil 19 operates on an armature 21 which is mechanically connected, as diagrammatically indicated at 22, with a counter-and-lockout mechanism 23, which is indicated by block-diagram in Fig. 1. The counter-andlockout mechanism 23 is mechanically connected, as diagrammatically indicated at 24, so as to trip out the sectionalizer-contact 20 after a predetermined number of counts of fault-current surges followed by interruptions of the current through the coil or solenoid 19, the mechanism thereupon not only opening the contact 20 but also locking it out, or holding it open, so as to disconnect the power-service from the rest of the line, extending beyond the location of the sectionalizer (such as 17), until the fault can be located and corrected, after which the sectionalizer will be reclosed or reset by hand.

Our invention relates to the detailed construction of the several sectionalizers, such as 17 or 18, as shown in Fig. 2. The sectionalizer 17 is here shown as being enclosed within a metal tank 27, which is provided with an insulating liner 28, and which is surmounted by a top casting 29. The incoming line 15 enters through a bushing 31 which terminates inside of the tank. The circuit then continues, through a conductor 32, to the sectionalizer-coil 19. From the sectionalizer-coil 19, the circuit continues through a conductor 33 back underneath the bushing 31 for the incoming lead 15, and thence to the terminal 34 which constitutes one of the stationary contacts of the sectionalizer. Ordinarily, the sectionalizer has two bushings, each with its lead passing through the bushing, and each bushing terminates, at its bottom, in one of the stationary contacts of the sectionalizers, but since Fig. 2 shows an approximate central section through the sectionalizer, the second stationary contact is not visible in Fig. 2, but it is indicated in Fig. l at 35. The movable contact 20 is shown, in Fig. 2, as an inverted channel-shaped contact-bar or bridge which is slidably disposed on a pull-rod 36 and is so biased upwardly by means of a spring 30 which rests on a transverse pin 95 that it presses up against the underside of the stationary contacts 34 and 35, in the closed position of the sectionalizer, and which is lowered by gravity, to operate the sectionalizer, upon the release of the pull-rod 36, which is shown in the form of an upwardly extending insulating tube.

The counter-and-lockout mechanism 23 is segregated, ,in Fig. 2, into its component parts, consisting of the l'-obtainf-in-air,with'the necessary time-constants.

counter or other tripping-mechanism 37, and the operating-mechanism 38.

vis sometimes desirableforthe'counter37 5topper'ate in-il,

A-as Y`itlinvolves Yda'shpotx -orfluid-ow -operation,f= as subsevquently described, which is somewhat'imore 'rliiiieulltllto 1t 1s sometimesdesirable tohave'the contacts-M-l-'E-S'S 'also 'operatingin oil. `lWehave consequentlyillust-rated our f apparatus,l by way `of eXample,- as -havingthe counter 37 and the 'contacts' 34420-135 4immersed :in oil'lit which is vcontainedin the y-tankf27.

According vto our linvention, -the operating-mechanism "SSis mountedin a framef41--1which is boltedtothefunderside ofthe-top casting 29. This operatingmechan-ism38 vmay'be regarded as-'starting :with-the movablefconta'ctmember v20, f and 'including' the' upwardly vlvextending invsulating'pull-rod36, ithefbottorn endzof Awhich vfis-oonrnected to said* movable' contact-member. "Pivotally lconnected,atl42, to lthevtop yof -fthe pull-rodf36, --is one ofthe two terminal' pivot-points' otra rocker-memberenlever-43, which is shown, lin its'preferred'form, as a' triangular ^-1plate, disposed *withl "its'base-'linel vnearly horizontal, with rtwo-terminal pivot-points '142' and l44- disposed-'near"the endsof` said base-line, and having an upwardly extending apex-portion lwhich carries-zan"intermediate rocker-point l45,'-which ispivotally.connected-tolalrst'endoflasnormal- "lyf nearly horizontal link-F46, which willi be subsequently l lfdescribed. ',The secondftermin'al .pivot-pointllfi"ofi-the rocker-member 43 is pivotally connected to an intermedi- Vatepointin a-normally nearly'-horizontalflatch!47, one end v of which -is'connected lto -a'- stationary pivotal support-48- rEhe intermediate' pivot-point--44 of' the ilatchf 47- is closer wtofthe pivotal lsupportffdfor the latch' thanto the' free fendwof the latch. Theffree end of the'y latch carries a roller '49.which -is mounted ona horizontal'pivotipin'fS. Inlthenormal closed position of Vthe-mechanism, the latch 47 eXterids-inan approximately horizontal direction, and its roller149'rests on the top of an upwardly extendling arm 52of an-approximately right-angled'bllcrank trigger 53, which 'is `pivotally 'mounted ion a` stationary pivotal support 54. The triggerSS-alsobasa-normally IapproximatelyV horizontal arm 55-having adownwardly facingabutment-sideS for engagement` by anupwardly :movable trip-pinf7 of the counter or'othertrippingr-means 37. The-vtrip-pin`f57is progressively stepped upwar'dly in response -to movementl ofthefarmature 21-asfa result 4of repeated- -energizations f lthefcil T19, as def scribed in 'detail in fthe-copending application Serial No. =196,508 of IamesM. Wallace and Andrew 'W.-`Edwards, iiiiled November 18,71950,-and trigger 53 is normally Vbiased to its'vlatching position,l as just described,'this bias being provided either by :gravity or bya spring'SS, or both.

A 'stop-Slengagingthe frame-41determinesthe latching a rposition of the trigger '53,

Thelink 46,fwhichf-isjpivoted Aat 'one end 45 tof the top of the triangular'rocker-member43,has a second 'end which is pivoted, rat/'59, to Vthe Ainner endzf an operating-.handle 60. An ir'iterinediate4 point ofthe-operating- "handle 60 is secured to a stationary `pivotal -supportfL v`whioh'is carried withinthe top castingf29. Thev outer end of the operating-handle i60 normally'pressesup against `anabutment 62 which is'carried by the underside of the top plate of the top casting 29.

ln accordance -with our invention, we `also provide a Areset-abutment 63 against' which the lower edge yof the vtriangular roller-member43 is engaged' inthe open posiltion'of the mechanism. Conveniently, as shown, th-isreset-abutmentisprovided byfa roller, or a stationary enlargg'portion, 63, onk the stationary pivot`54 for the trig- 'ger 4The operation ofthe operating-mechanism 3S is'shown vmore in detail in Figs. 3, 4 and'5, which respectively show theclose'd, tripped, and open positions of the linkage- -assembly of said operating-mechanism.

In the normal or closed position ofthe Alinkage, Vas shown -in Fig. 3, the link 46. is in toggle-lockwith respect Ato y'theoperating-handle60. In other-words,` the common `intermediate pivotal point orovercenter toggle-point 59 'of vthis 'toggle-linkage'6t-46-is some X52 of an inch below ,-the line joining the two terminal-pivots 61 and 45 of this toggle, so that weight or other opening-bias of the -rnov .able contact-member'20'tends to rock the rocker-member L43 in a counter-clockwisedireetioniabout itssecondtermivabovei'theA upright arm`52- :ofA the` trigger.53. Thusgwhen nal pivot-point 44, so that said rocker-member presses the -link-46-toward mtheoPeratng-handle-60 --in -such -direction that most of the thrust is taken by the pivotal support 61 of the operating-handle, but a small part of said thrust is transmitted to the abutment 62 for said operating-handle, in the normal closed position of the mechanism. The weight. or other biasing-force of .the movable contactmember 20 is borne bythe latch 47, .which is supported at its respective ends 49 and 4S.

Fig. 4 shows the .tripped position of the operatinglink- .age,in an intermediate stage. of theopening-operating of the-movable contact-memberZtl. The tripping-operation is initiated by an upward pressure of the trip-pin 57 (Fig. 2) against the horizontal arm 55 of the trigger 53. The tripping-movement of the trigger S3 in a counter-clockwise direction removes the support from the free end 49 of the latch 47, `so'thatthe weightofthe movable contactmember 20, pulling on the pull-rod 36, is transmitted by the rocker-.member-43 'to'the latch'47, 'and causes the ..infFig. 4. This downwardImovernent of fthelat'ch is acvnompaniedl byialdownward movement of the intermediate rocker-point145 lof .the lrocker-member 43, soias to" break -Lthe .toggle-flock-'with the-operating-handle; 69 .at the; pivot- Vpointdhasis showncin Fig.f4,fwherein.it"is seen .that the i'point'i59fis now'above'tthe :line-drawn between the 'two -Lterminal-pvots L61 and 45. of fthistoggle.

vAtionexpointfduringA the yopening movement :of the movable contact-member 24F, the rocker-irnember -"43 moves down farenough tohave :its lower edge come into of'the'xnechanism. During thiscounterclockwise' tilting 'of the'rocker-.memben'the 's econd terminal 'pivot-point'44 ofthe rocker-member 4lifts'the latch 47. up.' to a position the trip-pin 57v falls backout of engagement with the .trigger 1.53, 'the gravity or other` biasing means .ofthe triggerfSS causes the triggertto fall'. back .into its normal'position, l:with ithe 'fupright `arm 52 vin ,position .to receive the 'Idownaward thrust of the'freerend of the .latch '47, when jweight vis againplaced on said latch.

.Tozclose the' breaker, the outerend--ory handle-portion i of the operating-handle V:60 must Abe elevated, and this -movementlof the handle depresses the .inner end 59 thereof and causes the link 46 to rock the rocker-member 43 ina clockwise direction about its' second terminal pivot 44,

4which promptly; putsa-downward thrust on'lthe latch-47,

bringing the latch-roller 49 against the top of the yupright '..arm'52 of the' trigger`53, and' causingtheparts to return to theclosed position shown in Fig. 3.

If the sectionalizer-contact 2t) is manuallyopened, not

`by atrippingaction as just described, but byl a manual openingemovementofthe operating-handle 60, the Jrst beginning of said movement elevates the inner .pivot-point 59 of the operating handle and breaks the toggle atfthis place, which islshown in Fig. l, after/which .the weight of -iirst terminal pivot-point 42 of the rocker-memberl 43 in line with the pull-rod 36. This force F, produces a positive or counterclockwise moment +F, D, tending to rotate Ythe rocker-member 43 about its second terminal pivot- `point 44. This positive moment --F, D, is exactly opposed by the link i6 which applies a orceFg operating -on the intermediate rocker-point 45' in line with said `link 46, and producing a negative or clockwise moment -FaDz tending to rotate the rocker-member 43 about its aforesaid second terminal pivot-point 44. 'In Fig. 6, the iir'st lmoment-arm D,is substantially twice as long-as the second moment-arm D2, and lhence the second forceFz is substantially twice as large as the contact-bias F1. Constructing a force-triangle of the forces F1 andy F2, as indicated at 510i). we can '-nd .the direction-andthe magnitude -of "the resultant force Fs, which we can draw in, at the second terminal pivot-point 44, as shown in Fig. 3. This completes the force-diagram for the triangular rocker-member 43 in Fig. 6

The resultant-force F3 acts on the latch 47 to produce a positive or counterclockwise moment -l-FaDs tending to rotate the latch 47 about its stationary or fixed pivot 48 as shown in Fig. 6. This positive moment +F3D3 is exactly opposed by the upright trigger-arm 52 which applies a force F4 operating upwardly on the free end 49 of said latch 47 in a line which passes through the trigger-pivot 54, and producing a negative or clockwise moment -F4D4 tending to rotate the latch 47 about its pivot 48. It is a desirable feature of our invention that the resultant-force Fa should be in such a direction that its moment-arm D3 will be quite small as compared with the effective length D4 of the latch 47. In Fig. 6, the resultant moment-arm D3 is about one-seventh of the latch-length D4 (or even considerably less), and hence the latch-pressure F4 is small, only about one-seventh of the resultant force F3.

The precise counter or tripping-means 37 is an improved form of counter which constitutes the subject-matter of a companion application of J. M. Wallace and A. W. Edwards, Serial No. 196,508, filed November S, 1950. It is an essential feature of our invention, however, that this counting or tripping-mechanism 37, whatever its details, is suspended on long tubular insulators 70 which depend from the top of the top casting 29, so as to provide adequate insulation between the bottom 71 of the countermechanism 37, and the tank of our sectionalizer-mechanism. The lower end 71 of the counter-mechanism 37 is provided with a groove 92, which serves as a means for receiving a pivot-pin 93 which is thus positively located in a vertical direction with respect to the counter-mechanism 37. The pin 93 is used as a stationary pivot for pivotally supporting one end of each of a pair of insulating guidelinks 94, the other ends of which are pivoted to the lower end of the pull-rod 36, as shown at 95. This link-guiding or suspension of the lower end of the pull-rod 36 guides the substantially vertical movement of the moving contact-member during its opening movement, and at the same time insulates the contact-member 20 from the lower end 71 of the counter-mechanism 37, which is in turn insulated from the top casting 29 by the long vertical insulators 70. The vertical insulators 70 provide adequate insulation for the pivoted ends 93 of the guide-link insulators 94, and hence the guide-link insulators constitute a particularly desirable guiding-means for a mechanism which is gravity-operated, as in our preferred construction as illustrated. The top end of the insulating pull-rod 36 is held by pin 42 with freedom of substantially vertical movement by the rocker-member 43 of the operatingmechanism 38, which serves as a guide-link for that end of the pull-rod, in a known manner.

While we have illustrated our invention in but a single exemplary form of embodiment, which is now preferred, we wish it to be understood that our invention is susceptible of considerable modification, by way of additions, omissions and the substitution of various equivalents, without departing from the essential spirit of our invention, particularly in its broader aspects. We desire, therefore, that the appended claims shall be accorded the broadest construction consistent with their language.

We claim as our invention:

l. A latch-operated contact-separating mechanism, comprising the combination, with a movable contact-member which is normally closed but biased toward its open position, of a pull-rod connected at its first end to said movable contact-member, a rocker-member having two terminal pivot-points and an intermediate rocker-point, a first one of said terminal pivot-points of said rocker-member being pivotally connected to the second end of said pull-rod, a link having a first end pivotally connected to said intermediate rocker-point of said rocker-member, a latch, a stationary pivotal-supoprt-for one end of said latch, the second terminal pivot-point of said rocker-member being pivotally connected to an intermediate point in the latch, closer to said stationary pivotal support for the latch than to the free end of the latch, a trigger having an arm normally abutting against the free end of the latch to hold said mechanism in its normal closed position, a stationary pivotal support for said trigger, said trigger having an abutment-side for engagement by a trip-pin to disengage said latch-holding arm of the trigger from said latch, an operating-handle, a stationary pivotal support for said operating-handle, the inner end of said operatinghandle being pivotally connected to the second end of said link, means for providing an abutment to be engaged by said operating-handle in the closed position of the mechanism, and means for providing a reset-abutment to be engaged by an intermediate point of said rocker-member, intermediate between the two terminal pivot-points thereof, in the open position of the mechanism; said link being normally in toggle-lock with respect to said operatinghandle, so that the bias-action of said normally closed movable contact-member tends to rock said rocker-member about its second terminal pivot-point, so that said rocker-member presses said link toward said operatinghandle in such direction that most of the thrust is taken by the pivotal support of the operating-handle but a small part of said thrust is transmitted to the abutment for said operating-handle, in the normal closed position of said mechanism; said toggle-lock, with respect to the operating-handle, which is existent in the normal position of the mechanism, being broken in the tripped position wherein the trigger is disengaged from the latch, and the biasaction of the movable contact-member, which causes said movable contact-member to move in its opening direction, thereby assisting in causing said pull-rod to pull said rocker-member and hence said latch and the rst end of said link in such direction as to break said toggle-lock, the continued opening movement of said movable contact-member causing said intermediate portion of said rocker-member to engage its aforesaid reset-abutment, whereafter the still further continuing opening movement rocks said rocker-member about said reset-abutment and thus opens the operating-handle and causes the latch to swing back past said latch-holding arm of the trigger.

2. A normally closed circuit-make-and-break device,

' comprising: stationary contact-means; a movable contactmember which is normally closed against said stationary contact-means, said movable contact-member being biased, however, toward its open position; an insulatedly supported tripping-means having a trip-pin; a pair of insulating guide-links, pivoted at one end to said tripping-means and pivoted at the other end to said movable contact-member to guide the same in its opening-movement; and an operating-mechanism comprising a pull-rod connected at its first end to said movable contact-member, a rockermember having two terminal pivot-points and an intermediate rocker-point, a iirst one of said terminal pivotpoints of said rocker-member being pivotally connected to the second end of said pull-rod, a link having a tirst end pivotally connected to said intermediate rocker-point of said rocker-member, a latch, a stationary pivotal support for one end of said latch, the second terminal pivot-point of said rocker-member being pivotally connected to an intermediate point in the latch, closer to said stationary pivotal support for the latch than to the free end of the latch, a trigger having an arm normally abutting against the free end of the latch to hold said mechanism in its normal closed position, a stationary pivotal support for said trigger, said trigger having an abutment-side for engagement by said trip-pin to disengage said latch-holding arm of the trigger from said latch, an operating-handle, a stationary pivotal support for said operating-handle, the inner end of said operating-handle being pivotally connected to the second end of said link, means for providing an abutment to be engaged by said operating-handle in the closed position of the mechanism, and means for providing a reset-abutment to be engaged by an intermediate point of said rocker-member, intermediate between the two terminal pivot-points thereof, in the open position of the mechanism; said link being normally in toggle-lock with respect to said operating-handle, so that the bias action of said normally closed movable contact-member tends to rock said rocker-member about its second terminal pivotpoint, so that said rocker-member presses said link toward said operating-handle in such direction that most of the thrust is taken by the pivotal support of the operatinghandle but a small part of said thrust is transmitted to the abutment for said operating-handle, in the normal closed position of said mechanism; said toggle-lock, with respect to the operating-handle, which is existent in the normal position of the mechanism, being broken in the tripped position wherein the trigger is disengaged from the latch, and the bias action of the movable contact-member, which causes said movable contact-member to move in its opening direction, thereby assisting in causing said pull-rod to pull said rocker-member and hence said latch and the 4irstend of `said vlink in such .directionas to break said va movable contact-member which is norm-ally closed against the bottom of said stationary contact-means, the weight of said movable contact-member kand of its connected parts constituting a gravity-bias tending to open said movable contact-member; a tripping-means having an upwardly movable trip-pin; downwardly extending insulating supports-for suspending said tripping-means from the top of the circuit-make-and-break device; a pair of in- -sulating guide-link, pivoted at one end to said trippingmeans and pivoted at the other end to said movable contact-member to guide the same in its opening-movement; and an operating-mechanism comprising an upwardly extending insulating pull-rod connected at its bottom to said movable contact-member, a rocker-member having two terminal pivot-points and an intermediate rocker-point, a irst one of said terminal pivot-points of said rockermember being pivotally connected to the upper end of said pull-rod, a normally approximately horizontal link having a iirst end pivotally connected to said intermediate rockerpoint of said rocker-member, a normally approximately horizontal latch, a stationary pivotal support for one end of said latch, the second terminal pivot-point of said rocker-member being pivotally connected to an intermediate point in the latch, closer to said stationary pivotal support for the latch than to the free end of `the latch, a trigger having an upwardly extending arm normally abutting against the free end of the latch to hold said mechanism in its normal closed position, a stationary pivotal support for said trigger, said trigger having an abutment-side for engagement by said trip-pin to disengage said upwardly extending arm of the trigger from said latch, a normally approximately horizontal operating-handle, a stationary pivotal support for said operating-handle, the inner end of .said operating-handle being pivotally connected to the second end of said link, means for providing an abutment to be engaged by said operating-handle in the closed position of the mechanism, and means for providing a resetabutment to be engaged by an intermediate point of a lower edge of said rocker-member, intermediate between the two terminal pivot-points thereof, in the open position of the mechanism; said link being normally in toggie-lock with respect to said operating-handle, so that the bias-action of said normally closed movable contact-member tends to rock said rocker-member about its second terminal pivot-point, so that said rocker-member presses said link toward said operating-handle in such direction that most of the thrust is taken by the pivotal support of the operating-handle but a small part of said thrust is transmitted to the abutment for said operating-handle, in the normal closed position of said mechanism; said togglelock, with respect to the operating-handle, which is existent in the normal position of the mechanism, being broken in the tripped position wherein the trigger is disengaged from the latch, and the bias-action of the movable contact-member, which causes said movable contactmember to move downwardly in its opening direction, thereby assisting in causing said pull-rod to pull said rocker-member and hence said latch and the irst end of said link downwardly so as to break said toggle-lock, the continued opening movement of said movable contactmember causing said intermediate portion of said rockermember to engage its aforesaid reset-abutment, whereafter the still further continuing opening movement rocks said rocker-member about said reset-abutment and thus opens the operating-handle and causes the latch to swing back upwardly past the upwardly extending arm of the trigger.

4. The invention as dened in claim 1, characterized by said intermediate rocker-point being offset out of alignment with two terminal pivot-points of said rockermember.

5. The. invention as defined in claim 2, characterized by said intermediate rocker-point being offset out of alignmentr with two terminal pivot-points of said rockermember.

6. The invention astdenedin claim 3, lcharacterized by said intermediate rocker-point being o'tfset above the line joining the .two terminal pivot-points of the rockermember.

7. A latch-operated contact-separating mechanism, comprising the combination, with a movable contactmember which is normally closed but biased toward its open position, ofa pull-rod connected at its .rst end'to said movabie contact-member, a rocker-member having two terminal pivot-points and an offset intermediate rocker-point, out of alignment with the two terminal pivotpoints, a first one of said terminal pivot-points of said rocker-member being pivotally connected to the second end of said pull-rod, a link having a iirst end pivotally connected to said oifset intermediate rocker-point of said rocker-member, a latch, a stationary pivotal support for one end of said latch, the second terminal pivot-point of said rocker-member being pivotally connected to the latch at such a point that the resultant of the pull-rod force and the link force, applied to the latch at said point, has a latch-operating moment-arm which is short as compared to the eltective length of the latch, a trigger having an arm normally abutting against the freeend of the latch to hold said mechanism in its normal closed position, a stationary pivotal support for said trigger, said trigger having an abutment-side for engagement by a trip-pin to disengage said latch-holding arm of the trigger from said latch, an operating-handle, a stationary ypivotal support for said operating-handle, the inner end of said operating-handle being pivotally connected to the second end of said link, means for providing an abutment to be engaged by said operating-.handle in the closed position of the mechanism, and means for providing a reset-abutment to be engaged by an intermediate point of said rocker-member, intermediate between the two terminal pivot-points thereof, in the open position of the mechanism; said link being normally in toggle-lock with respect to said operating-handle, so that the bias-action of ,said normally closed movable contactmember tends to rock said rocker-member about its second terminal pivot-point, so that said rocker-member presses said link toward said operating-handle in such direction that most of the thrust is taken by the pivotal support of the operating-handle but a small part of said thrust is transmitted to the abutment for said operating-handle, in the normal closed position of said mechanism; said togglelock, with respect to the operating-handle, which is existent in the normal position of the mechanism, being broken in the tripped position wherein the trigger is disengaged from the latch, and the bias-action ofthe movable contactmember, which causes said movable contact-member to move in its opening direction, thereby assisting in causing said pull-rod to pull said rocker-member and hence said latch and the first end of said link in such direction as to break said toggle-lock, the continued opening movement of said movable contact-member causing said intermediate portion of said rocker-member to engage its aforesaid reset-abutment, whereafter the still further continuing opening movement rocks said rocker-member about said resetabutment and thus opens the operating-handle and causes the latch to swing back past said latch-holding arm of the trigger.

8. A normally closed circuit-make-and-break device, comprising: stationary contact-means; a movable contactmember which is normally closed against said stationary contact-means, said movable contact-member being biased, however, toward its open position; an insulated supported ripping-means having a trip-pin; a pair of insulating guidelinks, pivoted at one end to said tripping-means and pivoted at the other end to said movable contact-member to guide the same in its opening-movement; and an operating-mechanism comprising a pull-rod connected at its first end to said movable contact-member, a rocker-member having two terminal pivot-points and an olset intermediate rocker-point, out of alignment with the two terminal pivot-points, a iirst one of said terminal pivot-points of said rocker-member being pivotally connected to the second end of said pull-rod, a link having a first end pivotally connected to said offset intermediate rocker-point of said rocker-member, a latch, a stationary pivotal support for one end of said latch, the second terminal pivot-point of said rocker-member being pivotally connected to the latch at such a point that the resultant of thepull-rod force and the link force, applied to the latch at said point, has a latch-operating Amoment-arm which is short as compared to the eiective length. of the. latch, a trigger having an arm normally abutting against the free end of the latch to hold said mechanism in its normal closed position, a stationary pivotal support for said trigger, said trigger having an abutment-side for engagement by said trip-pin to disengage said latch-holding arm of the trigger from said latch, an operating-handle, a stationary pivotal support for said operating-handle, the inner end of said operating-handle being pivotally connected to the second end of said link, means for providing an abutment to be engaged by said operating-handle in the closed position of the mechanism, and means for providing a reset-abutment to be engaged by an intermediate point of said rocker-member, intermediate between the two terminal pivot-points thereof, in the open position of the mechanism; said link being normally in toggle-lock with respect to said operating-handle, so that the bias-action of said normally closed movable contact-member tends to rock said rocker-member about its second terminal pivot-point, so that said rocker-member presses said link toward said operating-handle in such direction that most of the thrust is taken by the pivotal support of the operating-handle but a small part of said thrust is transmitted to the abutment for said operatinghandle, in the normal closed position of said mechanism; said toggle-lock, with respect to the operating-handle, which is existent in the normal position of the mechanism, being broken in the tripped position wherein the trigger is disengaged from the latch, and the bias-action of the movable contact-member, which causes said movablecontact-member to move in its opening direction, thereby assisting in causing said pull-rod to pull said rocker-member and hence said latch and the tirst end of said link in such direction as to break said toggle-lock, the continued opening movement of said movable contact-member causing said intermediate portion of said rocker-member to engage its aforesaid reset-abutment, whereafter the still further continuing opening movement rocks said rockermember about said reset-abutment and thus opens the operating-handle and causes the latch to swing back past said latch-holding arm ofthe trigger.

9. A normally closed, gravity-operated, circuit-makeand-break device, comprising: a stationary contact means: a movable contact-member which is normally closed against the bottom of said stationary contact-means, the weight of said movable contact-member and of its connected parts constituting a gravity-bias tending to open said movable contact-member; a tripping-means having an upwardly movable trip-pin; downwardly extending insulating supports for suspending said tripping-means from the top of the circuit-make-and-break device; a pair of insulating guide-links, pivoted at one end to said tripping means and pivoted at the other end to said movable contactmember to guide the same in its opening-movement; and an operating-mechanism comprising an upwardly extending insulating pull-rod connected at its bottom to said movable contact-member, a rocker-member having two terminal pivot-points and an oset intermediate rocker-point, out of alignment with the two terminal pivot-points, a first one of said terminal pivot-points of said rocker-member being pivotally connected to the upper end of said pullrod, a normally approximately horizontal link having a lirst end pivotally connected to said oiset intermediate rocker-point of said rocker-member, a normally approximately horizontal latch, a stationary pivotal support for one end of said latch, the second terminal pivot-point of said rocker-member being pivotally connected to the latch at such a point that the resultant of the pull-rod force and the link force, applied to the latch at said point, has a latch-operating moment-arm which is short as compared to the effective length of the latch, a trigger having an upwardly extending arm normally abutting against the free end of the latch to hold said mechanism in its normal closed position, a stationary pivotal support for said trigger, said trigger having an abutment-side for engagement by said trip-pin to disengage said upwardly extending arm of the trigger from said latch, a normally approximately horizontal operating-handle, a stationary pivotal support for said operating-handle, the inner end of said operatinghandle being pivotally connected to the second end of said link, means for providing an abutment to be engaged by said operating-handle in the closed position of the mechanism, and means for providing a reset-abutment to be engaged by an intermediate point of a lower edge of said rocker-member, intermediate between the two terminal pivot-points thereof, in the open position of the mechanism; said link being normally in toggle-lock with respect to said operating-handle, so that the bias-action of said normally closed movable contact-member tends to rock said rocker-member about its second terminal pivotpoint, so that said rocker-member presses said link toward said operating-handle in such direction that most of the thrust is taken by the pivotal support of the operatinghandle but a small part of said thrust is transmitted to the abutment for said operating-handle, in the normal closed position of said mechanism; said toggle-lock, with respect to the operating-handle, which is existent in the normal position of the mechanism, being broken in the tripped position wherein the trigger is disengaged from the latch, and the bias-action of the movable contact-member, which causes said movable contact-member to move downwardly in its opening direction, thereby assisting in causing said pull-rod to pull said rocker-member and hence said latch and the first end of said link downwardly so as to break said toggle-lock, the continued opening movement of said movable contact-member causing said intermediate portion of said rocker-member to engage its aforesaid reset-abutment, whereafter the still further continuing opening movement rocks said rocker-member about said reset-abutment and thus opens the operatinghandle and causes the latch to swing back upwardly past the upwardly extending arm of the trigger.

l0. A circuit-interrupter comprising fixed contactmeans, a movable contact-member adapted to be moved into and out of engagement with said fixed contact-means, an insulating operating-rod movable longitudinally to actuate said movable contact-member, two sets of pivotedlink mechanisms connected to the operating rod on opposite sides of the movable contact-member and longitudinally spaced along the rod for separately guiding the respective ends of said operating-rod during the movement of said movable contact-member, and means comprising a manually operable toggle linkage connected to the link mechanism more remote from the contact-member for actuating the contact-member into and out of engagement with said fixed contact-means.

ll. A circuit-interrupter comprising fixed contactmeans, a movable contact-member adapted to be moved substantially upwardly into engagement with said fixed contact-means and substantially downwardly out of engagement therewith, a substantially vertically extending insulating pull-rod having its lower end secured to said movable contact-member, a gravity-operated operatingmechanism comprising a pivoted member which serves as a guide-link for holding the top end of said pull-rod with freedom of substantially vertical movement, manual operating means connected to said member, an electrically controlled tripping-mechanism having a frame and having an advanceable member adapted to trip said operating-mechanism in response to repeated overcurrents only, insulating supporting-means for the frame of said tripping-mechanism, and an insulating guide-link connected between the lower end of said pull-rod and said frame of the tripping-mechanism for holding said lower end with freedom of substantially vertical movement.

l2. In a circuit interrupter, a pair of spaced stationary contacts, a movable contact disposed to bridge the stationary contacts, an operating mechanism including a lever havmg two terminal points and an intermediate point of connection, an insulating rod having a yieldable connection with the movable contact connected to one of said terminal points, releasable means including a support lever pivotally supported and pivotally connected to the aforesaid lever at the other terminal point disposed to support said other terminal point, and manually operable means connected to said intermediate point of connection for operating the lever to move the movable contact into and out of engagement with said stationary contacts.

1.3. A circuit interrupter comprising, a pair of spaced stationary contacts, a lever mechanism including a lever having a pair of spaced terminal points, an insulating pull rod pivotally connected to one of the terminal points, a channel-shaped bridging contact slidably disposed on the pull rod and having spring means to bias it toward the stationary contacts, releasable means including a support lever and a latch therefor disposed to support said other terminal point, and manual operating means connected to said lever intermediate said terminal points.

14. A circuit interrupter comprising, stationary contact means, a lever mechanism including a lever having two terminal points and an intermediate point of connection, an insulating rod connected to one of said terminal points,

an inverjted channel-shaped contact member slidably disposed on the rod to engage said stationary contact means, a spring disposed on theV rod within the channel-shaped contact means, releasable means including a support pivotally supporting the other terminal point of the lever and a latch therefor, and a manually operable toggle mechanism connected to said intermediate point of connection for actuating said vlever to effect separation and engagement of said channel-shaped contact member and said stationary Contact means.

15. A circuit interrupter comprising, separable contact means, an operating mechanism for said contact means comprising, a toggle means having a first undercenter position when said contact means are closed and movable to another overcenter position when said contact means are opened, said toggle means having two links each with two terminal pointsand an intermediate pivot point, a terminal point of one link and the intermediate point of the other comprising a common pivot point, electroresponsive trip means having a movable trip member for displacing one of said terminal points to move said toggle means from its rst undercenter position to its other overcenter position, and a handle connected to one of said links for moving it to effect relative displacement of said common pivot point and thereby moving said toggle means to its other overcenter position.

16. A circuit interrupter comprising, separable contact means biased to the open position, an operating mechanism for said contact means comprising a toggle means of two links, one having a terminal pivot point, releasable means normally holding saidpivot point stationary, a common intermediate pivot point for said linkshaving a rst overcenter position when said contact means are closed and movable to its other overcenter position when said contact means are opened, electromagnetically controlledv tripping means having a movable trip pin disposed to displace said releasably held terminal point and thereby move said intermediate pivot point from its first overcenter position to, said other overcenter position, and an extension on onejof said links for manually displacing said intermediate-pivot point to either of its overcenter positions.

17. A circuit interrupter comprising, separable Contact means, an operating mechanism for said contact means comprising a toggle means of two linkseach having two terminal points and a common intermediate pivot point whichqhas a rst overcenter pesi'ton whenzsaid contact means are closed'and another overcenter positionwhen they are opened, releasable meansoperable to support :one

of said terminal pivot points, electromagnetically con;l

trolled tripping means having-a movable ltrip member opf erable to actuate said releasable means and displace said one terminal point to move the intermediate pivot point from its rst overcenter position to its other overcenter position, means for resetting said releasable means during opening of said contact means to restore it to its terminal point supporting condition, and manually operableA Number Name Date 823,984 Acly JunelQ, 1906 1,030,568 Cheney June 25, 1912 1,132,772 Harris- Mar. 23, 1915 1,837,805l Ainsworth .Dec. 22, 1931 2,086,628 Matejka July 13, 1937 2,150,307 Wulsten Mar. 14,' 1939 2,246,298 Dyer et al. June 17, 1941 2,283,795 Dahl May 19, 1942 2,333,604 Wallace ,Nov. 2, 1943 2,414,796 Bresson Jan. 28, 1947 2,434,096 Ayers et al. Jan. 6, 1948 2,455,067 Kyle, Jr., et al. Nov. 3,0, 1948 2,459,327 Kyle lan. 18, 1949 2,468,852 Wallace et al. May 3, 19.49 2,480,161 Prescott Aug. 30,y 1949- 2,5l5,530 Schindler July 1S, 1950 2,528,197. Wallace Oct. 31, 1950 2,530,298 Harper Nov. 14, 1950 2,560,529 Van Ryan I uly l0, 1951 FOREIGNy PATENTS Number Country. Date 415,413 Great Britain. Aug. 2 1, 19:34

OTHER REFERENCES AIEE Technical1Haper.47-50, November- 1946. 

